The present invention applies to scaffolds, particularly useful for adjustable-height scaffolds; and except for a novel safety feature for providing safety against inadvertent pin release, the invention relates to adjustable-height scaffolds such as set forth in the said Patent and the said Applications, especially as to a combination embodying a latch-release lever such as set forth in the Applications.
Such scaffolds have a spring-pressed pin to hold the platform to the scaffold legs, and the spring provides some safety of maintaining latch-pin engagement.
Further safety against inadvertant latch-pin withdrawal is provided by a screwthread feature, in that Patent and both Applications, of mating screwthreads provided respectively on the latch-pin assembly and on the support bushing for the latch pin; and, with that type of safety feature, latch-pin withdrawal is effectively blocked.
As noted further herein, however, such a screw-thread safety feature has long been realized to have certain disadvantages, particularly of improper use, lack of proper maintenance, rough handling, etc., and, in considerable contrast to that screwthread feature, the present invention provides novel concepts and components for automatically blocking latch-release withdrawal of the latch pin except when the latch pin is being intentionally disengaged, yet automatically releases the latch pin for withdrawal from the scaffold leg when latch-disengagement is being intentionally desired and achieved.
Thus, great advantage over the prior art is provided, against whatever might be the cause or cause-contribution to inadvertent pin-release, such as a weak or broken spring, a forgetting by the user to engage the screwthread safety, accidental bumping or jarring, etc.; and much less maintenance need be provided, and much less safety instruction and procedural policies need be administered, etc.